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Two-dimensional Analysis (two-dimensional + analysis)
Selected AbstractsInfluence of particle shape and angularity on the behaviour of granular materials: a numerical analysisINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2003C. Nouguier-Lehon Abstract This paper analyses the influence of grain shape and angularity on the behaviour of granular materials from a two-dimensional analysis by means of a discrete element method (Contact Dynamics). Different shapes of grains have been studied (circular, isotropic polygonal and elongated polygonal shapes) as well as different initial states (density) and directions of loading with respect to the initial fabric. Simulations of biaxial tests clearly show that the behaviour of samples with isotropic particles can be dissociated from that of samples with anisotropic particles. Indeed, for isotropic particles, angularity just tends to strengthen the behaviour of samples and slow down either local or global phenomena. One of the main results concerns the existence of a critical state for isotropic grains characterized by an angle of friction at the critical state, a critical void ratio and also a critical anisotropy. This critical state seems meaningless for elongated grains and the behaviour of samples generated with such particles is highly dependent on the direction of loading with respect to the initial fabric. The study of local variables related to fabric and particle orientation gives more information. In particular, the coincidence of the principal axes of the fabric tensor with those of the stress tensor is sudden for isotropic particles. On the contrary, this process is gradually initiated for elongated particles. Copyright © 2003 John Wiley & Sons, Ltd. [source] Insight into the flow-condition-based interpolation finite element approach: solution of steady-state advection,diffusion problemsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 2 2005Haruhiko Kohno Abstract The flow-condition-based interpolation (FCBI) finite element approach is studied in the solution of advection,diffusion problems. Two FCBI procedures are developed and tested with the original FCBI method: in the first scheme, a general solution of the advection,diffusion equation is embedded into the interpolation, and in the second scheme, the link-cutting bubbles approach is used in the interpolation. In both procedures, as in the original FCBI method, no artificial parameters are included to reach stability for high Péclet number flows. The procedures have been implemented for two-dimensional analysis and the results of some test problems are presented. These results indicate good stability and accuracy characteristics and the potential of the FCBI solution approach. Copyright © 2005 John Wiley & Sons, Ltd. [source] Development of a convection,diffusion-reaction magnetohydrodynamic solver on non-staggered gridsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 11 2004Tony W. H. Sheu Abstract This paper presents a convection,diffusion-reaction (CDR) model for solving magnetic induction equations and incompressible Navier,Stokes equations. For purposes of increasing the prediction accuracy, the general solution to the one-dimensional constant-coefficient CDR equation is employed. For purposes of extending this discrete formulation to two-dimensional analysis, the alternating direction implicit solution algorithm is applied. Numerical tests that are amenable to analytic solutions were performed in order to validate the proposed scheme. Results show good agreement with the analytic solutions and high rate of convergence. Like many magnetohydrodynamic studies, the Hartmann,Poiseuille problem is considered as a benchmark test to validate the code. Copyright © 2004 John Wiley & Sons, Ltd. [source] Quantitative two-dimensional analysis of facial wrinkles of Japanese women at various agesINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2002K. Tsukahara Synopsis To evaluate individual differences in the recognition of facial wrinkles, we asked 40 Japanese female observers to identify wrinkles using transparent sheets over frontal facial photos of four females aged 20, 39, 55 or 75 years. We then measured the number and length of those wrinkles by image analysis. Wrinkles identified by those 40 observers showed aged-related increases in the standard deviation (SD) values for number and length but age-related decreases in the coefficient of variation (CV)%. Therefore, to clarify factors affecting the degree of wrinkle detection, wrinkles were identified by two groups of age-matched male and female observers, by two groups that differed by age, and by two other groups, one of which who felt that there was an improvement in their wrinkles after application of an antiwrinkle agent and another group who did not feel that there was any improvement after the same treatment. Improvement was observed by replica image analysis in all groups. The degree of wrinkles identified was not affected by the age or by the sex of the observer group. However, the group who felt that there was an improvement in their wrinkles after treatment with the antiwrinkle agent identified a significantly higher number of wrinkles than did the group who did not feel that there was an improvement. These results suggest marked individual differences in the recognition of wrinkles. Fine wrinkles in relatively young subjects are difficult to detect, but moderate to marked wrinkles in middle-aged and in aged subjects can easily be detected. Concerning the cause of individual differences in the extent of wrinkle detection, observers who identified a large number of wrinkles tended to recognize not only pronounced wrinkles but also recognized fine wrinkles as ,wrinkles'. This seems to have also affected their feelings about the success of treatment with the antiwrinkle agent. Résumé Pour pouvoir évaluer les différences individuelles dans la l'identification des rides faciale, nous avons demandéà 40 femmes japonaises d'identifier des rides en utilisant des feuilles transparentes sur des photos faciales frontales de quatre femmes, âgées respectivement de 20, 39, 55 et 75 ans. Nous avons alors mesuré le nombre et la longueur de ces rides par analyse d'images. Les rides identifiées par ces 40 femmes montraient que le vieillissement qui s'y rattachait augmentait selon les valeurs d'un écart standard (ES) pour le nombre et la longueur, mais que le vieillissement qui s'y rattachait diminuait dans le pourcentage du coefficient de variation. Par conséquent, pour clarifier les facteurs affectant le degré de détection des rides, ces dernières furent identifiées par deux groupes d'hommes et de femmes dont l'âge coïncidait, âgés de 26,6 ans et de 44,5 ans, et par deux autres groupes. Un groupe qui a estimé qu'il y avait eu une amélioration dans les rides après une application de 6 semaines d'un agent antirides aux coins des yeux et un autre groupe qui a considéré qu'après le même traitement il n'y avait pas eu d'amélioration. Une amélioration fut remarquée par la copie d'une analyse d'images dans tous les groupes. Le degré d'importance des rides identifiées n'était pas affecté par l'âge ou le sexe des groupes étudiés. Cependant, le groupe qui a estimé qu'il y avait eu une amélioration concernant leurs rides après un traitement avec un agent antirides a identifié un nombre significativement plus élevé de rides que le groupe qui estimait qu'il n'y avait pas eu d'amélioration. Ces résultats suggèrent des différences individuelles notoires dans l'identification de rides. De minces rides dans les groupes relativement jeunes sont difficiles à déceler. Mais des rides modérées remarquées dans les groupes de personnes d'un,ge moyen et, âgées peuvent être facilement localisées. Concernant la cause de ces différences individuelles dans l'importance d'un décèlement des rides, les sujets qui identifièrent un grand nombre de rides avaient tendance à ne pas prononcer le mot ,rides', mais trouvaient que de fines rides n'étaient que des ,rides'. Cela semblait aussi affecter leurs sentiments après le succès du traitement avec des agents antirides. [source] Small-angle X-ray scattering study of intramuscular fish bone: collagen fibril superstructure determined from equidistant meridional reflectionsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2008Christian Burger New insights into the bone collagen fibril superstructure have been obtained by novel small-angle X-ray scattering analysis. The analysis was carried out on the small-angle equidistant meridional reflections resulting from the periodic structure of collagen fibrils in their axial direction. Conventional two-dimensional analysis is difficult because of the large discrepancy of longitudinal and lateral length scales for individual fibrils, as well as their preferred orientation. The new approach represents an unapproximated analysis of the equidistant meridional reflections, which takes the exact separation of preferred orientation and fibril size effects into account. The analytical results (e.g. axial period, fibril diameter etc.) agree well with the parameters obtained from transmission electron microscopy. [source] | ||||||||||